Biology 189 EXAM 2 |156 questions with
Solutions
Explain how catabolism and anabolism are linked. How is ATP involved in these processes?
How do endergonic and exergonic reactions relate to catabolism & anabolism? - -
Catabolism: is an exergonic reaction because it releases energy (ATP).
-breakdown of fuel.
Anabolism: is an endergonic reaction because it requires energy (breaks ATP by
hydrolysis=ADP which is used to build.
-build macromolecules.
-How is synthesis of ATP and hydrolysis (breaking) of ATP related to the 1st and 2nd laws
of thermodynamics? - -The synthesis of ATP is related to the 1st law of thermodynamics
because it involves the transfer of electrons, you can't create or destroy energy only
transform.
The hydrolysis of ATP is related to the 2nd law of thermodynamics because it involves the
concept of entropy. You are breaking glucose into smaller molecules, releasing energy and
resulting in increased entropy.
-How could you represent respiration on a graph?* Where do you position the reactants
relative to the products? What is the formula for respiration (inputs and outputs)? - --On a
graph the products are low compared to the reactants (downhill).
glucose+oxygen---> carbon dioxide+water+ATP
(C6H12O6 + 6O2---> 6CO2 + 6H2O + 36 ATP) -aerobic respiration.
-How are oxidation & reduction reactions related to the process of cellular respiration? - -
The pathways of aerobic respiration oxidize (remove electrons from) glucose and reduce
(add electrons to) O2.
-Why does cellular respiration only have a 37% energy efficiency? - -37% of the energy
stored in the bonds of a glucose molecule is stored as ATP. The rest goes to waste as heat.
-We discussed four stages of respiration: what are the four stages? What is the proper
order of the four stages? Where does each stage take place within a cell? Which stage(s)
require O2? Which stage is oxygen-independent? - -In order:
1. glycolysis: takes place in the cytosol,
-Oxygen independent
2. transition step: takes place in the cytosol (prokaryotic) and mitochondrion matrix
(eukaryotic).
-Requires O2.
3. krebs cycle: takes place in the cytosol (prokaryotic) and mitochondrion matrix
(eukaryotic).
-Requires O2.
,4. electron transport chain: takes places in the cell membrane (prokaryotic) and the
mitochondrion inner membrane-cristae (eukaryotic).
-Requires O2.
-Walk me through glycolysis. Where does it take place in the cell? What are the inputs?
What are the outputs? Where do these outputs go relative to the rest of the stages of
cellular respiration (what is their role?)? What is the difference between total number of
molecules synthesized and net gain?* - -A six-carbon glucose molecule splits into two
three-carbon molecules of pyruvate. First, some of the electrons from glucose are
transferred to an electron carrier molecule called NADH. Second, glycolysis generates two
molecules of ATP.
-input: 1 glucose, 2 NAD+, 2 ADP+2P
-output: 2 three-carbon, 2 NADH, 2 ATP
-The 2 NADH and 2 ATP go the electron transport chain.
-There is a net gain of 2 ATP
-Occurs in the cytosol in both prokaryotic and eukaryotic cells.
-Walk me through pyruvate oxidation. Where does it take place in the cell? What are the
inputs? What are the outputs? Where do these outputs go relative to the rest of the stages
of cellular respiration? Why can one of these outputs potentially be used in the Calvin cycle
of photosynthesis (what stage of photosynthesis?)? Why must the cell perform pyruvate
oxidation twice every time one glucose is processed in glycolysis? - --occurs in the
mitochondrial matrix. After glycolysis.
-input: two 3-carbons and two NAD+
output: two 2 acetyl~CoA, 2 CO2, and 2 NADH
-NADH goes to the ETC and CO2 is released.
-A molecule of CO2 is removed and NAD+ is reduced to NADH. The remaining two-carbon
molecule, called an acetyl group, is transferred to a molecule called coenzyme A to form
acetyl coenzyme A (abbreviated acetyl CoA). Acetyl CoA is the compound that enters the
Krebs cycle and the 2 NADH and 2 ATP go to the electron transport chain.
-CO2 can potentially be used in the Calvin cycle of photosynthesis stage 1 because it
contains carbon.
-The cell must perform pyruvate oxidation twice because the product of glycolysis is 2
pyruvic acid molecules, they go in one at a time.
-Walk me through the Citric Acid Cycle (aka CAC or Krebs cycle). Where does it take place
in the cell? What are the inputs? What are the outputs? Where do these outputs go relative
to the rest of the stages of cellular respiration? Why can one type of these outputs
potentially be used in the Calvin cycle of photosynthesis (what stage of photosynthesis?)?*
Why must the cell perform the citric acid cycle twice every time one glucose is processed in
glycolysis?* - --Occurs in the cytosol for prokaryotic and mitochondrion matrix for
eukaryotic.
-Inputs: 2-acetyl~CoA, 2 ADP + 2 P, 6 NAD+, and 2 FAD.
Outputs: 4 CO2, 2 ATP, 6 NADH, and 2 FADH2.
-4 CO2 is a waste product but the rest (6 NADH, 2 FADH2) go to the electron transport
chain.
, -CO2 can be used in the first stage of the Calvin cycle of photosynthesis because it contains
carbon.
-The Krebs cycle must perform cycle twice because there are 2 acetyl-CoA that come out of
pyruvate oxidation, they go in the Krebs cycle one at a time.
-Walk me through the electron transport chain (ETC). Where does it take place in the cell?
What are the inputs? What are the outputs?* Can you draw the series of molecules needed
in the ETC? The placement is important; do you know the order of these components? Be
sure to label: Enzyme complexes I, II, III, IV H2O, ADP, P, ATP, NAD+, NADH, FAD, FADH2,
H+, mobile protein I, mobile protein II, ATP synthase, O2, e- (electrons). What is the source
of electrons to keep the ETC going? The "stripping" or oxidizing of these molecules leads to
the formation of what? What component is responsible for stripping this molecule of its
electrons to keep the ETC going? What does this component do with the electrons? Why
does this component need these high-energy electrons?* Once they have accomplished
their task, whom do these components give these electrons to in the ETC? Why are these
electrons analogous to "hot potatoes"? - --occurs in the cell membrane in prokaryotic cells
and in the mitochondrion inner membrane-cristae in eukaryotic cells. Also occurs in the
thylakoid membranes of chloroplasts.
-Inputs: 6 NADH and 2 FADH2.
Outputs: 6 CO2 + 6 H2O + 36 ATP.
-The source of electrons to keep ETC going is NADH and FADH2.
-The oxidizing of these molecules form NAD+ and FAD.
-The component responsible for oxidizing NADH and FADH2 is enzyme complex I and II.
-This component moves electrons down the electron transport chain. once the last member
of the electron transport chain is done and holding the ground-state electrons, they give it
to oxygen and end up forming water.
-They are analogous to hot potatoes because every time the electrons move, they lost
energy.
-Why is a concentration gradient of H+ (protons) important in the ETC? Which
components in the ETC are directly responsible for maintaining the proton gradient? How
do they do this? Hint: Why could we nick name these components proton pumps? Why is
this considered a form of active transport? How do these components "pay" to perform this
active transport? Which molecule relies on facilitated diffusion of protons to perform its
reactions? What reaction does this component catalyze?* Why are the products of this
reaction so important to the cell (how is it related to anabolism?)? - --It is important
because the H protons provide energy to the ATP synthase which uses the facilitated
diffusion to let in all the H+'s to make ATP.
-The components responsible for this are the enzyme complexes, they do this by taking a
portion of energy from the moving electrons and pump them through the protein.
-active transport because it requires ATP (the payment).
-Hydrogen ions relies on facilitated diffusion by ATP synthase.
-
-The product from ATP synthase is ATP which is important to the cell. It is related to
anabolism because it is building the ATP.
Solutions
Explain how catabolism and anabolism are linked. How is ATP involved in these processes?
How do endergonic and exergonic reactions relate to catabolism & anabolism? - -
Catabolism: is an exergonic reaction because it releases energy (ATP).
-breakdown of fuel.
Anabolism: is an endergonic reaction because it requires energy (breaks ATP by
hydrolysis=ADP which is used to build.
-build macromolecules.
-How is synthesis of ATP and hydrolysis (breaking) of ATP related to the 1st and 2nd laws
of thermodynamics? - -The synthesis of ATP is related to the 1st law of thermodynamics
because it involves the transfer of electrons, you can't create or destroy energy only
transform.
The hydrolysis of ATP is related to the 2nd law of thermodynamics because it involves the
concept of entropy. You are breaking glucose into smaller molecules, releasing energy and
resulting in increased entropy.
-How could you represent respiration on a graph?* Where do you position the reactants
relative to the products? What is the formula for respiration (inputs and outputs)? - --On a
graph the products are low compared to the reactants (downhill).
glucose+oxygen---> carbon dioxide+water+ATP
(C6H12O6 + 6O2---> 6CO2 + 6H2O + 36 ATP) -aerobic respiration.
-How are oxidation & reduction reactions related to the process of cellular respiration? - -
The pathways of aerobic respiration oxidize (remove electrons from) glucose and reduce
(add electrons to) O2.
-Why does cellular respiration only have a 37% energy efficiency? - -37% of the energy
stored in the bonds of a glucose molecule is stored as ATP. The rest goes to waste as heat.
-We discussed four stages of respiration: what are the four stages? What is the proper
order of the four stages? Where does each stage take place within a cell? Which stage(s)
require O2? Which stage is oxygen-independent? - -In order:
1. glycolysis: takes place in the cytosol,
-Oxygen independent
2. transition step: takes place in the cytosol (prokaryotic) and mitochondrion matrix
(eukaryotic).
-Requires O2.
3. krebs cycle: takes place in the cytosol (prokaryotic) and mitochondrion matrix
(eukaryotic).
-Requires O2.
,4. electron transport chain: takes places in the cell membrane (prokaryotic) and the
mitochondrion inner membrane-cristae (eukaryotic).
-Requires O2.
-Walk me through glycolysis. Where does it take place in the cell? What are the inputs?
What are the outputs? Where do these outputs go relative to the rest of the stages of
cellular respiration (what is their role?)? What is the difference between total number of
molecules synthesized and net gain?* - -A six-carbon glucose molecule splits into two
three-carbon molecules of pyruvate. First, some of the electrons from glucose are
transferred to an electron carrier molecule called NADH. Second, glycolysis generates two
molecules of ATP.
-input: 1 glucose, 2 NAD+, 2 ADP+2P
-output: 2 three-carbon, 2 NADH, 2 ATP
-The 2 NADH and 2 ATP go the electron transport chain.
-There is a net gain of 2 ATP
-Occurs in the cytosol in both prokaryotic and eukaryotic cells.
-Walk me through pyruvate oxidation. Where does it take place in the cell? What are the
inputs? What are the outputs? Where do these outputs go relative to the rest of the stages
of cellular respiration? Why can one of these outputs potentially be used in the Calvin cycle
of photosynthesis (what stage of photosynthesis?)? Why must the cell perform pyruvate
oxidation twice every time one glucose is processed in glycolysis? - --occurs in the
mitochondrial matrix. After glycolysis.
-input: two 3-carbons and two NAD+
output: two 2 acetyl~CoA, 2 CO2, and 2 NADH
-NADH goes to the ETC and CO2 is released.
-A molecule of CO2 is removed and NAD+ is reduced to NADH. The remaining two-carbon
molecule, called an acetyl group, is transferred to a molecule called coenzyme A to form
acetyl coenzyme A (abbreviated acetyl CoA). Acetyl CoA is the compound that enters the
Krebs cycle and the 2 NADH and 2 ATP go to the electron transport chain.
-CO2 can potentially be used in the Calvin cycle of photosynthesis stage 1 because it
contains carbon.
-The cell must perform pyruvate oxidation twice because the product of glycolysis is 2
pyruvic acid molecules, they go in one at a time.
-Walk me through the Citric Acid Cycle (aka CAC or Krebs cycle). Where does it take place
in the cell? What are the inputs? What are the outputs? Where do these outputs go relative
to the rest of the stages of cellular respiration? Why can one type of these outputs
potentially be used in the Calvin cycle of photosynthesis (what stage of photosynthesis?)?*
Why must the cell perform the citric acid cycle twice every time one glucose is processed in
glycolysis?* - --Occurs in the cytosol for prokaryotic and mitochondrion matrix for
eukaryotic.
-Inputs: 2-acetyl~CoA, 2 ADP + 2 P, 6 NAD+, and 2 FAD.
Outputs: 4 CO2, 2 ATP, 6 NADH, and 2 FADH2.
-4 CO2 is a waste product but the rest (6 NADH, 2 FADH2) go to the electron transport
chain.
, -CO2 can be used in the first stage of the Calvin cycle of photosynthesis because it contains
carbon.
-The Krebs cycle must perform cycle twice because there are 2 acetyl-CoA that come out of
pyruvate oxidation, they go in the Krebs cycle one at a time.
-Walk me through the electron transport chain (ETC). Where does it take place in the cell?
What are the inputs? What are the outputs?* Can you draw the series of molecules needed
in the ETC? The placement is important; do you know the order of these components? Be
sure to label: Enzyme complexes I, II, III, IV H2O, ADP, P, ATP, NAD+, NADH, FAD, FADH2,
H+, mobile protein I, mobile protein II, ATP synthase, O2, e- (electrons). What is the source
of electrons to keep the ETC going? The "stripping" or oxidizing of these molecules leads to
the formation of what? What component is responsible for stripping this molecule of its
electrons to keep the ETC going? What does this component do with the electrons? Why
does this component need these high-energy electrons?* Once they have accomplished
their task, whom do these components give these electrons to in the ETC? Why are these
electrons analogous to "hot potatoes"? - --occurs in the cell membrane in prokaryotic cells
and in the mitochondrion inner membrane-cristae in eukaryotic cells. Also occurs in the
thylakoid membranes of chloroplasts.
-Inputs: 6 NADH and 2 FADH2.
Outputs: 6 CO2 + 6 H2O + 36 ATP.
-The source of electrons to keep ETC going is NADH and FADH2.
-The oxidizing of these molecules form NAD+ and FAD.
-The component responsible for oxidizing NADH and FADH2 is enzyme complex I and II.
-This component moves electrons down the electron transport chain. once the last member
of the electron transport chain is done and holding the ground-state electrons, they give it
to oxygen and end up forming water.
-They are analogous to hot potatoes because every time the electrons move, they lost
energy.
-Why is a concentration gradient of H+ (protons) important in the ETC? Which
components in the ETC are directly responsible for maintaining the proton gradient? How
do they do this? Hint: Why could we nick name these components proton pumps? Why is
this considered a form of active transport? How do these components "pay" to perform this
active transport? Which molecule relies on facilitated diffusion of protons to perform its
reactions? What reaction does this component catalyze?* Why are the products of this
reaction so important to the cell (how is it related to anabolism?)? - --It is important
because the H protons provide energy to the ATP synthase which uses the facilitated
diffusion to let in all the H+'s to make ATP.
-The components responsible for this are the enzyme complexes, they do this by taking a
portion of energy from the moving electrons and pump them through the protein.
-active transport because it requires ATP (the payment).
-Hydrogen ions relies on facilitated diffusion by ATP synthase.
-
-The product from ATP synthase is ATP which is important to the cell. It is related to
anabolism because it is building the ATP.
